Run time calculation in g-code program properties

I wonder how EMC calculates the run time shown in g-code program properties. It's always far less than the actual run time required.
Seems that it's usually half the actual time, but I can't figure this out exactly.

It only sums the time to make the moves and does not take acceleration/deceleration into account which would make the actual timelonger.

John

This explains it. You know if there are any plans on making this calculation less fictional?

I don't know of anything in the works, the number is an exact time for each move less the things listed below.

Short of running the g code on a sim with my timer component to get exact time you would pretty much have to duplicate the trajectory planner and a whole bunch of other code I assume to get exact times due to the many factors involved which include the naive cam detector which may combine short lines and arcs into one and the G61/64 setting among others as well as the acceleration and max velocity of each axis.

John

I understand. I think that at least taking into account the acceleration / deceleration would be something good.
I don't think I'm up to it with the development skills I have, but I'll take a look at the source code anyway and see if I could make any improvements.

It starts on line 1693 of / src/emc/usr_intf/axis/scripts/axis.py

LOL, at least I can find it...

Dunno if this line is a clue to getting the acceleration values

mf = vars.max_speed.get()

But if they are different... that would get complicated pretty fast.

John

BigJohnT wrote: It starts on line 1693 of / src/emc/usr_intf/axis/scripts/axis.py

LOL, at least I can find it...

Dunno if this line is a clue to getting the acceleration values

mf = vars.max_speed.get()

But if they are different... that would get complicated pretty fast.

John

HI
Is there any progress in the development of a more accurate time calculation?

Tom

To my knowledge no one is working on this as accurate time calculations can be arrived at by running a sim with the exact same configuration as the machine. Of course your welcome to work on it.

The time component will give you the run time when you run a file.

www.linuxcnc.org/docs/html/man/man9/time.9.html

JT

Can I see run time calculation value in the Axis GUI?
If not, is it possible to create Python Virtual Control Panel widget to show this value?
Thanks.

If you want a run timer that is easily done with a VCP. A run time estimator would be difficult and there is already one built into Axis.

There are example configurations look up the man for time.9 it has example pyvcp code.
linuxcnc.org/docs/html/man/man9/time.9.html